Sled-brake



(Model) M, HOFFMAN.

SLED BRAKE.

No. 254,318; I Patented Feb. 28. 11882..

Fwyrl j UNITED STATES MICHAEL HOFFMAN, OF LORETTO, PENNSYLVANIA.

PATENT OF ICE.

SLED-BRAKE.

SPECIFICATION forming part of Letters Patent No. 254,318, dated February 28, 1882,

Application filed Ap'ri11,1881. (ModeL) To all whom it may concern:

Be it known that I, MICHAEL HOFFMAN, of Loretto, in the county of Oambria and State of Pennsylvania, have invented certain new and useful Improvementsin Automatic Brakes for Sleds, 850.; and I do hereby declare that the following is a full, clear, and exact description of the invention,which will enable others skilled in the art to which it appertains to make and use the same, reference being bad to the accompanying drawings, which form a part of this specification, and in which Figure 1 is a plan or top view of the front bob of a sled or sleigh provided with my automatic brake. Fig. 2 is a longitudinal vertical section of the same; and Fig. 3 is a perspective detail view of one end of the transverse rock-shaft with its operating-arms and brake-rods.

Similar letters of reference indicate corresponding parts in all the figures.

My invention has relation to that class of sled-brakes which will set themselves as the sled goes down hill or when the team is suddenly stopped, while they are released or let go automatically when the sled is on level ground or going up hill, or when the team is started; and it consists in the improved construction and combination of parts, as hereinafter more fully described, and particularly pointed out in the claim.

In the annexed drawings, A represents the runners, B the knees, G the benches, and D the fenders, of a sled, or of the front bob of a sled.

E is the tongue to which the hitching-chain (not shown in the drawings) is attached, and which passes through a loop or keeper, F, secured in the front cross-bar, O, which prevents lateral play of the tongue without interfering with its free forward and backward motion. The rear end of the tongueis out off abruptly, as shown at e, and has boltedto its under side a flat iron bar, G, the rear end of which passes through a keeper, h, and terminates in a crossbar, H. At opposite ends of said cross-bar are links or rods I I, which connect with the downward-projectiu g arms K of a rock-shaft, L, which is hung in bearings M M secured in one of the benches 0. That part of the rockshaft between its bearings is made square in cross-section, as shown in the drawings, for the purpose of the better attachment of its arms K, through the squarely-perforated heads of whichthe rock-shaft is inserted. At each end of rock-shaft L, between its bearings M and arms K, is another arm, N, which projects at right angles, or nearly so, to the arms K. In the outer ends of these arms N are pivoted the brake-bars O, the lower ends of which are inserted through keepers P, secured on the inner side of the runners, and are cut off obliquely to form the brake points or shoes 19.

By reference to Fig. 2 of the drawings it wilt be seen that the brakes O are not set parallel to the knees B, but slant or incline backward from top to bottom, for the purpose hereinafter set forth in describing the operation of the brake.

The bench (3, immediately in front of the cross-bar H, has a bolt-hole, Q, which is set to one side of the tongue-bar G, and the bottom ofthesled,which is supported upon the benches,

-(but not shown in the drawings,) has a registering aperture, through which a headed bolt, B, may be inserted into the bolt-hole Q.

When the sled is on level ground or going bear up against the cut off rear end, 6, of the tongue, thus tilting the rock-shaft L, with its arms N, and forcing the pointed ends of the brakes or brake-bars 0 down into the ground.

By setting the brakes O obliquely in the manner described, they will, when set as represented in dotted lines in Fig. 2, never be in a line with their connecting-arms N, so as to form a dead-center, which, by the weight and downward pressure of the sled and its load, would be apt to bind, and thus affect the easy and instantaneous operation ofthe brake mechanism, and after the brakes have been once set they and their operating mechanism are relieved from further strain by the rear end of the tongueE bearing against thefront bench, 0.

If desired, the rear end of the tongue which passes through the keeper F may be made with two or more notches, ff, in its upper face, for looking it in any given position upon said keeper by the means of a wedge inserted underneath it (the tongue) when it is desired to throw the brake mechanism out of play, or vice-versa. In backing the bolt R is removed 5 to permit the cross-bar H to pass the bolt-hole, after which the bolt is reinserted back of the cross-bar, which looks the brake in its off position and prevents setting.

desired the bolt is of course reinserted in its 10 former position.

Having thusdescribed my invention, I claim and desire to secure by Letters Patent of the United States- In a sled-brake, the combination, with the 15 automaticallyoperating or self-setting brake After backing as mechanism, composed of the oblique brakes O O, rock-shaft L, having arms N N and K K, connecting-links I I, T-shaped cross-head G H, and sliding tongue E e, constructed and arranged as described, of the movable bolt R, in- 20 

